jQuery MagicLine Navigation

Avatar of Chris Coyier
Chris Coyier on (Updated on )

These “sliding” style navigation bars have been around a while, I just thought I’d take a crack at doing it myself as the opportunity came up recently. Turns out it’s really pretty darn easy. I put two examples together for it.

The Idea

The idea is to have a highlight of some kind (a background or an underline) follow you around as you mouse over the different links in the navigation. This will happen with jQuery and it’s animation abilities. As such, the “magic line” will only be appended via JavaScript. Once added to the list and styled, as you mouse over the different links, it figures out the left positioning and the width and animates to match.


Typical list here… It has the “group” class because it’s going to be a horizontal row and will need the clearfix so it has height. The ID is for the JavaScript to target it.

<nav class="nav-wrap">
  <ul class="group" id="example-one">
    <li class="current_page_item"><a href="#">Home</a></li>
    <li><a href="#">Buy Tickets</a></li>
    <li><a href="#">Group Sales</a></li>
    <li><a href="#">Reviews</a></li>
    <li><a href="#">The Show</a></li>
    <li><a href="#">Videos</a></li>
    <li><a href="#">Photos</a></li>
    <li><a href="#">Magic Shop</a></li>

Notice the .nav-wrap div around it. That is used because of the styling, the bars go full width of the screen the but the navigation is centered within. This centering brings up an issue when we start the JavaScript.


Do the ol’ inline list elements with floated left anchors to get the list horizontal and avoid stairstepping. The magic line is absolutely positioned under the bar, so that it doesn’t cause jitter (mouse over a link, animates over, mouse is now on magic line not the link, animates back, etc.) Everything else is purely stylistic.

.nav-wrap { margin: 50px auto;  background-color: rgba(0, 0, 0, 0.6); border-top: 2px solid white; border-bottom: 2px solid white; }
#example-one { margin: 0 auto; list-style: none; position: relative; width: 960px; }
#example-one li { display: inline; }
#example-one li a { color: #bbb; font-size: 14px; display: block; float: left; padding: 6px 10px 4px 10px; text-decoration: none; text-transform: uppercase; }
#example-one li a:hover { color: white; }
#magic-line { position: absolute; bottom: -2px; left: 0; width: 100px; height: 2px; background: #fe4902; }

jQuery JavaScript

  1. When DOM is ready…
  2. Set up variables including current left offset of the navigation
  3. Set up resize function on the window to reset that offset should it change (because of the centering)
  4. Append the magic line to the nav
  5. Set up position and width of the magic line for the current page item
  6. Also set the original width and position as data, so it can be used to animate back to
  7. On hover, calculate the new width and new left position and animate to it
  8. On the hover callback (mouse out), animate back to original

Updated, thanks to smart comments by Daniel and Nora Brown below.

$(function() {

    var $el, leftPos, newWidth,
        $mainNav = $("#example-one");
    $mainNav.append("<li id='magic-line'></li>");
    var $magicLine = $("#magic-line");
        .css("left", $(".current_page_item a").position().left)
        .data("origLeft", $magicLine.position().left)
        .data("origWidth", $magicLine.width());
    $("#example-one li a").hover(function() {
        $el = $(this);
        leftPos = $el.position().left;
        newWidth = $el.parent().width();
            left: leftPos,
            width: newWidth
    }, function() {
            left: $magicLine.data("origLeft"),
            width: $magicLine.data("origWidth")


See the Pen
jQuery MagicLine
by Chris Coyier (@chriscoyier)
on CodePen.


Opera is weird about it. It makes the original width of the magic line the full width of the nav bar and shortens it from the right on hovers. I haven’t been able to figure it out. If you do, awesome, let me know I’ll update this article and demos.

Alternate Version

Check out the demo link below for an alternate version that uses a background instead of a line, and animates color as well as position and width. Basically the same, except the CSS is slightly different and the JavaScript pulls the color of the new list item from a rel attribute in the HTML.

Color animations in jQuery require the color plugin. I was just moaning about how it doesn’t work with RGBa color, and someone sent me a patch that does, which is included in the download. I’m really sorry, but I can’t remember their name! Speak up if it was you and I’ll update this and credit the patch to you.

All Yours

As always, feel free to do whatever you want with it. Preferably, use it in corporate projects and earn wheelbarrows of cash.

Updated on April 27, 2011 to work better with IE 6-10